1. Pratham, IITB Student Satellite Saptarshi Bandyopadhyay System Engineer, Pratham IIT Bombay 27 th August, 2008

2. "There are some who question the relevance of space activities in a developing nation. To us, there is no ambiguity of purpose. We do not have the fantasy of competing with the economically advanced nations in the exploration of the moon or the planets or manned space-flight. But we are convinced that if we are to play a meaningful role nationally, and in the community of nations, we must be second to none in the application of advanced technologies to the real problems of man and society. "

3. Indian Space Research Organization  Over 40 years of experience in space.  31 Indian satellites successfully launched.  Indigenous profitable launch vehicles.  We are going to the Moon!

4. Student satellite – The Idea!  The aim is to develop a satellite which can be made within a time frame of two or three years, be of low cost, low mass (< 10kgs) and launch it into orbit.  Use of COTS instruments to reduce costs.  Success of the mission attached to process of learning and not just the final output.  ‘The first Cubesat was used as an technology evaluation mission’ – AAU Cubesat mission statement 1.MINI – SPUTNIK 2.ASUSAT 3.NCUBE 4.SSETI 5.AAU Cubesat 6.SNOE 7.ICARUS 8.CATSAT 9.DTUSAT 10.MEROPE 11.COMPASS 12.SEEDS

6. Grand Plan for the Student Satellite Project at IIT Bombay!  We wish to make IIT Bombay a respected center for advancement in Satellite Technology, in the world.  We should launch at least 5 satellites within the next 20 years.  The Satellites could be test-beds for new technology that is being developed in the institute and need space qualification. We need success in our first Mission!!

7. The IITB Student Satellite Team for Pratham Year Number of Students Fifth year1 Fourth Year4 Third Year13 Second Year15 Department Number of Students Aerospace9 Engineering Physics 4 Electrical11 Computer Science3 Mechanical2 Civil1 Chemical3 Sub-SystemNumber of Students Payload4 Communication6 Attitude Determination and Controls 5 On Board Computer7 Power5 Structures and Thermals 5 System Engineer1

8. List of Professors  Prof K. Sudhakar (Aero)  Prof H. Arya (Aero)  Prof P. M. Mujumdar (Aero)  Prof S. P.Bhat (Aero)  Prof K. Chatterjee (Elec)  Prof B. G. Fernandes (Elec)  Prof K. N. Iyer (Mech)  Prof R. K.Pant (Aero)  Prof K. K.Isaac (Mech)  Prof U.N.Gaitonde (Mech)  Prof R.K.Shevgaonkar (Elec)  Prof R. N. Banavar (Elec)  Prof Madhu N. Belur (Elec)  Prof V. Ramgopal Rao (Elec)  Prof D.K.Sharma (Elec)  Prof Krithi Ramamritham (CS)  Prof Subhananda Chakrabarti (Elec)

9. Mission Statement for Pratham  Acquiring knowledge in the field of Satellite and Space Technology.  Develop the Satellite through the phases of Design, Analysis, Fabrication and Testing.  Launch the satellite, Measure TEC of the Ionosphere and create TEC map of India.  Involve students from other universities in our Satellite project.

10. Timeline for Pratham till now PeriodDescription August 07Concept feasibility proved to the Aerospace Department Sept – Oct 07IITB Satellite Team was selected Dec 07First trial at modeling satellite subsystems Jan – Apr 08Detailed study of all subsystems with TEC and Thermopile as Payload for the satellite. Requirements capture report was written. May 08 – July 08 TEC has been finalized as the only Payload. Conceptual Design Phase finished. August 08 – Present Preliminary Design Phase. Engineering Model will be built.

11. Documentation and Reviews  Major Emphasis on Documentation.  We want to preserve our knowledge.  Regular review done by the team and faculty.  Reports written and circulated within the team.  Reviews done in ISAC and other ISRO scientist.  All our documents are available on our website  For Password: Contact any of the people mentioned in the Contacts List (On website)

12. Payload  Total Electron Count of the Ionosphere  Method used for measuring TEC on our Satellite:  Faraday rotation  linearly polarized radio waves at 405MHz and 437MHz  Difference in polarization measured on ground using crossed yagi.  TEC maps of India  Ionosphere Tomography (?)

13. Social Goal The greater the number of ground stations, greater is the number of locations at which TEC will be recorded. We plan to approach universities across India requesting them to serve as a ground station for our satellite. This will motivate the participating students and get them interested in satellite technology.

14. Communication and Ground Station  Low bit rate Beacon. (Freq = 437MHz)  High bit rate (1.2kbps) Monopole for downlink of data. (Freq = 405MHz)  We do not have uplink  Linearly polarized radio signals.  2 crossed yagis at ground stations to receive data and measure their polarization.  PDR  Simulation of onboard Monopoles and circuit  Ground Stations for IITB, Tomography and Social Goal

15. Attitude Determination and Controls Goal  To stabilize the satellite after deployment and to maintain the 3 axis attitude of the satellite within Functional Requirements  Detumbling Mode  Nominal Operation Mode  Emergency Mode Control law  Linear controller Sensors  GPS (1)  Single Rate gyro (3)  Single axis sun sensor (6)  Magnetometer (1) Actuators  Magnetorquer (3) PDR  Hardware  Software

16. On Board Computer Hardware  Microcontroller  Atmel AT91M40080  PROM  One time programmable EPROM AT27BV040  NVRAM  TI bq4015LYMA-70N Software  Stages of Operation  Minimal pre-empting of running task  Cyclic Scheduler PDR  Hardware  Software

17. Power Systems  Major power inputs  Direct solar radiation  Solar radiation reflected from Earth (albedo)  Earth’s thermal radiation  Average useful power incident on the faces. AA’BB’CC’Tot 21W7W17W 20W2W84W Hardware  Solar cells  Batteries  3.3V regulator  5V regulator  Microcontroller  Power distribution  Battery protection  Power OR-ing diodes  RBF pin, kill and charging switches  PDR

18. Structures, Thermals and Mechanisms Structures  Weight budgeting  Qualification of the satellite structure as per launch loads  Qualification of structure based on thermal loads in orbit  Configuration Layout  Deployment of 2 parallel monopoles  PDR – Structure  PDR – Mechanisms Thermal  Maintain suitable temperature for components.  Temporal cycle of temperatures experienced in each orbit  Spatial gradient of temperature at an instant  Dissipation of heat from components onboard  Active thermal control of critical components  PDR - Thermals

19. System Engineer’s Tasks  Stages and Functions of Satellite  System and Sub-System Requirements  Budget for Weight, Power and Data  Interface, Connectors and Wires  Configuration Layout  Launch Vehicle Interface and Access Ports  PDR

23. Future Plan PeriodDescription Present – SeptPreliminary Design Phase (Engineering Model) Sept – Dec 08Detailed Design Phase (Qualification Model) Jan – Feb 09Prototype Testing and Qualification Phase Mar – April 09Flight Testing phase (Flight Model)

24. New Satellite  Thermal Imaging using the sensors developed by Prof Subhananda Chakrabarti (Elec).  Use of Mems sensors  Launch Vehicle Interface  Try uplink!...  Team starts work by December 2008  Satellite should be launched by 1 st quarter 2010

25. Inducting new Students  Quiz (24 th September)  Student Satellites  Our Reports  Sub-System specific For registering mail: shashanktamaskar@iitb.ac.in  Presentation (October)  Members become formal in Dec 08  System Engineering  Payload  Communication  Controls  On Board Computer  Power  Structures  Thermal  Mechanisms